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ENDOMEMBRANE SYSTEM ORGANELLES: Endoplasmic Reticulum

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ENDOMEMBRANE SYSTEM ORGANELLES: Endoplasmic Reticulum About Science Prof Online PowerPoint Resources • Science Prof Online (SPO) is a free science education website that provides fully-developed Virtual Science Classrooms, science-related PowerPoints, articles and images. The site is designed to be a helpful resource for students, educators, and anyone interested in learning about science. • The SPO Virtual Classrooms offer many educational resources, including practice test questions, review questions, lecture PowerPoints, video tutorials, sample assignments and course syllabi. 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You must be in slide show mode to utilize hyperlinks and animations. •This digital resource is licensed under Creative Commons Attribution-ShareAlike 3.0: http://creativecommons.org/licenses/by-sa/3.0/ Alicia Cepaitis, MS Tami Port, MS Chief Creative Nerd Creator of Science Prof Online Science Prof Online Chief Executive Nerd Online Education Resources, LLC Science Prof Online [email protected] Online Education Resources, LLC [email protected] From the Virtual Biology Classroom on ScienceProfOnline.com Image: Compound microscope objectives, T. Port Biological Cell Structure & Function Images: M. Ruiz From the Virtual Biology Classroom on ScienceProfOnline.com Two Basic Types of Cells Prokaryotic Eukaryotic Cells Cells Cells: - are the building blocks of life! - All living things are made of one or more cells. WATCH THIS! - only come from other cells. Introduction to - are , really small. How small are they? Cell Video - small because of surface to volume ratio Images: Prokaryotic cell diagram & From the Virtual Biology Classroom on ScienceProfOnline.com Eukaryotic cell diagram, M. Ruiz Size of Living Things 1 m = 100 cm = 1,000mm = 1,000,000 µm = 1,000,000,000nm 1mm = 1000 µm = 1000000nm 1 µm = 1000nm Click link for an interactive “Size of Microscopic Things” animation on Cells Alive. From the Virtual Biology Classroom on ScienceProfOnline.com Old School 5 Kingdom classification of organisms Eukaryotes Prokaryotes From the Virtual Biology Classroom on ScienceProfOnline.com Image: Phylogenetic Tree, Wiki Binary Fission Prokaryotes (Bacteria) Tell me about Prokaryotes… Check out these quick animated lessons on binary fission: (Please watch both, as each provides different and useful information.) Binary Fission Animation from ClassZone Binary Fission Animation From McGraw-Hill Images: Prokaryotic cell diagram, M. From the Virtual Biology Classroom on ScienceProfOnline.com Ruiz, Binary fission, JW Schmidt Bacterial Genetics Nucleoid • Region of cytoplasm where prokaryote’s genome (DNA) is located. • Usually a singular, circular chromosome. Plasmid • Small extra piece of chromosome/genetic material. • 5 - 100 genes • Not critical to everyday functions. • Can provide genetic information to promote: - Antibiotic resistance - Virulence factors (molecules produced by pathogen that specifically influence host's function to allow the pathogen to thrive) - Promote conjugation (transfer of genetic material between bacteria through cell- to-cell contact) Image: Prokaryotic Cell Diagram: M. Ruiz, From the Virtual Biology Classroom on ScienceProfOnline.com Bacterial conjugation, Adenosine Prokaryotes Bacteria Cytoplasm • Also known as proto-plasm. • Gel-like matrix of water, enzymes, nutrients, wastes, and gases and contains cell structures. • Location of growth, metabolism, and replication. Granules • Bacteria’s way of storing nutrients. • Staining of some granules aids in identification. Image: Prokaryotic cell diagram: M. Ruiz, Granules, Source Unknown From the Virtual Biology Classroom on ScienceProfOnline.com Prokaryotes Bacteria Cytoskeleton Ø Cellular "scaffolding" or "skeleton" within the cytoplasm. Ø Major advance in prokaryotic cell biology in the last decade has been discovery of the prokaryotic cytoskeleton. Ø Up until recently, thought to be a feature only of eukaryotic cells. From the Virtual Biology Classroom on ScienceProfOnline.com Image: Prokaryotic Cell: M. Ruiz Prokaryotes Bacteria Ribosomes Ø Found within cytoplasm or attached to plasma membrane. Click here for animation of ribosome Ø Made of protein & rRNA. building a protein. Ø Composed of two subunits. Ø Cell may contain thousands . Ø Q: What do ribosomes do? Ø Q: What’s the relationship between the job that the ribosomes do and the genetic instructions (nucleic acids) of the cell? Animation: Ribosome translating protein,; From the Virtual Biology Classroom on ScienceProfOnline.com Xvazquez; Ribosome Structure, Vossman Prokaryotes Plasma Membrane Ø Separates the cell from its environment. Ø Phospholipid molecules oriented so that hydrophilic water-loving heads directed outward and hydrophobic water-hating tails directed inward. Ø Proteins embedded in two layers of lipids (lipid bilayer). Ø Membrane is semi-permeable. Q: What does that mean? From the Virtual Biology Classroom on ScienceProfOnline.com Image: Cell Membrane diagram, Dhatfield Bacterial Cell Wall Ø Peptidoglycan is a huge polymer of interlocking chains of alternating sugar monomers held together with peptide bridges. Ø Provides rigid support while freely permeable to solutes. Ø Two main types of bacteria cell wall. Gram-positive Gram-negative Image: Bonding structure peptidoglycan, From the Virtual Biology Classroom on ScienceProfOnline.com Mouagip; Gram-positive and Gram-negative bacteria @ 100xTM Bacterial Cell Wall Gram-Positive & Gram-Negative Q: Why are these differences in bacterial cell wall structure important? From the Virtual Biology Classroom on ScienceProfOnline.com Images: Sources Unknown Bacterial Endospores Ø Dormant, tough, non- reproductive structure produced by small number of bacteria. Ø Resistant to radiation, desiccation, lysozyme, temperature, starvation, and chemical disinfectants. Ø Endospores are commonly found in soil and water, where they may survive for very long periods of time. Image: Bacillus subtilis, SPO Science Image From the Virtual Biology Classroom on ScienceProfOnline.com Library; , Clostridium botulinum, PHIL #2107 Bacterial Genus : Clostridium GRAM-POSITIVE Obligate anaerobes bacillus-shaped endospore producer Ø The members of this genus have a couple of bacterial “superpowers” that make them particularly tough pathogens. Ø They produce endospores Ø Also produce a variety of toxins, some of which are fatal. - Clostridium tetani = agent of tetanus - C. botulinum = agent of botulism - C. perfringens = one of the agents of gas gangrene - C. difficile = part of natural intestinal flora, but resistant strains can proliferate and cause pseudomembranous colitis. Images: Man with Tetanus, Sir Charles Bell; Nails, Wiki; Wet Gangrene, Wiki From the Virtual Biology Classroom on ScienceProfOnline.com Prokaryotes Surface Appendages Ø Some prokaryotes have distinct appendages that allow them to move about or adhere to solid surfaces. Ø Consist of delicate stands of proteins. A couple example of prokaryotic surface appendages: Ø flagella: Long, thin extensions that allow some bacteria to move about freely in aqueous environments. (singular: flagellum) Ø fimbriae: Most Gram-negative bacteria have these short, fine appendages surrounding the cell. Gram+ bacteria don’t have. Help bacteria stick to solid surfaces. Major factor in virulence. (singular: fimbria) From the Virtual Biology Classroom on ScienceProfOnline.com Images: Helicobacter pylori; E. coli fimbriae, Manu Forero REVIEW! Here’s are two excellent interactive lessons: 1. Prokaryote Cell Structure from Cells Alive 2. Interactive Cell Structure from Wiley From the Virtual Biology Classroom on ScienceProfOnline.com Images: Prokaryotic cell diagram, M. Ruiz Eukaryotic Cells Ø Eu =“true”, karyon=“nucleus” Ø Genetic material contained in a nuclear membrane. Ø Membrane bound organelles. Ø Include animal, plant, fungi, algae cells as well as other microscopic eukaryotes. Ø Evolved from prokaryotic cells. From the Virtual Biology Classroom on ScienceProfOnline.com Image: Eukaryotic Cell Diagram, M. Ruiz Old School 5 Kingdom classification of organisms Eukaryotes Prokaryotes From the Virtual Biology Classroom on ScienceProfOnline.com Image: Phylogenetic Tree, Wiki Cytoplasm Nicknames: The Matrix, Molecular Chowder Ø Fills the space between the plasma membrane and the nuclear membrane Ø A water-like substance that fills cells. Ø Consists of cytosol and cellular organelles except for the cell nucleus. Ø cytosol is made up of water, salts, organic molecules and many enzymes that catalyze reactions. Q: Eukaryotes? Prokaryotes? Both? From the Virtual Cell Biology Classroom on ScienceProfOnline.com Image: Eukaryotic Cell Diagram, M. Ruiz Cytoskeleton Nicknames: Scaffolding, Highways • Maintains cell shape. • Protects the cell. • Enables some cell movement
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